The Role of Dietary Heavy Metal Exposure and Socio-Behavioral Factors in the Etiology of Chronic Kidney Disease of Unknown Origin (CKDu) in Anuradhapura, Sri Lanka

Globally, heavy metal exposure is one of the major toxic pollutant in the environment which cause severe diseases. Chronic Kidney Disease with unknown etiology (CKDu) is an irreversible disease and most challenging as its late indication of symptoms. Sri Lanka is being affected by CKDu since last couple of decades where dry zones especially Anuradhapura district of North Central Province is mostly affected by CKDu. This study puts contribution to identify the causes of CKDu of Sri Lanka by including chemical analysis on food items, social survey among both CKDu affected and non-affected groups. Heavy metal analyses of fish (muscle and liver parts) in eight locations from CKDu endemic region were carried out. The samples were collected from most CKDu affected places of Anuradhapura district, Sri Lanka. Higher concentrations of Cadmium (Cd) were found in fish muscles in three locations. Mean weekly intake of Cd of three locations exceeded the prescribed guidelines with highest weekly intake of Cd via fish of 12.8 µg/kg body weight (Medawachchiya) and mean weekly intake of Pb through fish exceeded FAO guidelines only in Padaviya. However, mean weekly intake of other metals via fish were found to be lower the relevant standards. Liver part of fish showed higher rate of accumulation for metals Zn, Mn, As and Cr in the most of the studied locations than muscles part of fish. Social survey says over 15 years agricultural experienced farmers age more than 41 years old, who have history of work more than 5 days in agriculture field with low water intake (less than 2 litres/day), consume fish more than 5 days per week, chew betel 4-6 times per day and consume local liquor more than 4 times per week showed high chance for CKDu development than others in Anuradhapura district, Sri Lanka.